Prick punching machine



A 1 M, D. FITZGERALD 1,925,034

PRICK PUNCHING MACHINE Filed July 2O, 1932 4 Sheets-Sheet 1 Aug. 29, 1933. M D FLTZ'GERALD 1,925,034

BRICK PUNCHING MACHINE Filed July 20, 1952 4 Sheets-Shet 2 1933- M. D.VFITZGERALD 1,925,034

PRICK PUNCHING MACHINE Filed July 20, 1932 4 Sheets-Sheet 3 Aug. 29, 1933.

PRICK PUNCHING MACHINE M. D. FITZGERALD 7 1,925,034

Filed July 20, 1932 4 Sheets-Sheet 4 Patented Aug,- 29, 1933 PRICJK PUNCHING MACHINE Martin D. Fitzgerald, Torrington, Conn, assignor to The Fitzgerald Mfg. Company, Torrington,

Conn,

a corporation of Connecticut Application July 20, 1932. Serial No. 623,637

6 Claims.

The present invention relates to improvements in apparatus for prick-punching sheet metal and like materials, wherein a large number of closely disposed perforations are made in a sheet with- 5 out removing any of the material from the sheet, by forming the perforations with outwardly extending burrs projecting from the edges thereof, the burrs from certain of the perforations extending from one face of the sheet and the burrs of other perforations extending from the other face of the sheet.

Such perforated sheets of material have a variety of uses, among which is that of forming a base for gaskets, and which base is provided on opposite sides with a lamina of asbestos fibre, rubber, or other materials. Of course, means may be provided so that the burrs may only extend from one side of the face of the sheet if desired.

The object of the present invention isto provide apparatus and method for manufacturing said perforated sheets in continuous production and in a very economical manner, yet with means which are reliable, durable and efficacious in operation. It is also an object of the invention to provide a machine and process for prick-punching sheet material of the character described, which will insure against deforming or fracturing the sheet, except at points of perforation, so as not to impair the strength of the sheet in the manu factured article.

With the above and other objects in view, the present invention resides in the sundry details of construction, combination and arrangement of parts hereinafter more fully describedand pointed out in the appended claims.

In the drawings, which show the preferred eznbodiments of the invention as at present devised:

Figure 1 is a side elevation of the machine of the present invention;

' Figure 2 is a transverse sectional view taken substantially on line 2-2 of Figure 1;

Figure 3 is a sectional view taken substantially on line 3-3 of Figure 2;

Figure 4 is a sectional view lyonlineHofFigurem Figure 5 is an enlarged front end view of the punches and dies and looking in the direction of the arrow of Figure 1, with the upper and lower punch and die members in normally raised or separated position;

Figure 6 is a vertical sectional view taken substantially on line 6-6 of Figure but showing cross head moved downwardly to bring the upper punch and die members in contact with the taken substantialsheet material and in a position about to perform said prick-punching;

Figure 7 is a similar view to Figure 6 showing the upper and lower punch and die members performing the punching operation;

. Figure 8 is an'enlarged sectional view taken substantially on line 88 of Figure 6 of the upper and lower die members only and in the position shown in Figure 6.

Figure 9 is an enlarged fragmentary view of the outer faces of the punch holder showing the grooves in which the heads of the punches are retained to prevent them from rotating out of proper position;

Figure 10 is a transverse sectional view taken substantially on line 1010 of Figure 5;

Figure 11 is a side elevation of a punch memher; i v

Figure 12 is a side elevation of said punch member looking at right angles in respect to Figure 11 and also illustrating the manner in which the punch end perforates the sheet material; and

Figure 13 is an end view looking to the pointed or punch ends of the punch elements shown in Figures 11 and 12.

Referring in detail to the drawings, the punch machine of the present invention comprises the usual frame having a bed 10 which may be supported in any suitable manner and side uprights 12 having a shaft 13 journaled in their upper portions. A cross-head 14 is mounted in vertical guideways 11, provided on the inner faces of said uprights and is reciprocated in said guideways on the movement of the shaft 13. Any suitable means may be employed for connecting the shaft with the cross-head. However, in the present instance, the shaft carries a cam or eccentric 15 around the periphery of which is a band or ring 16 to which is pivotally attached a pitman rod 17. The cross-head is formed with a chuck 18 in which may be mounted the shank 19 of a tool-- head 20. The tool-head 20 carri dies which cooperate with the punches and dies carried by the lower tool holder the base 10 of the machine, the being reciprocated in a vertical direction to perform the punching operation; While the sheet .material is not being perforated it is fed intermittently between said tool-heads.

upper tool-head es punches and 21 mounted on 10 An extension frame 22 is mounted or otherwise 5 provided on the rear end of the bed 10 and is provided at its extremity with bearings 23 in which is mounted a beam 24 for rotatably supporting a coil or reel ofsheet metal m, which is fed therefrom in the direction of the arrow, shown in Figure 2, between the tool-heads 20 and 21 and to a winding beam or shaft 25 mounted on the front end of the bed 10.

I The extension 22 preferably comprises two spaced arms rearwardly projecting from the base and having a pair of feeding rollers 27 and 28 mounted at their ends in vertically slotted bearings 26, one of said bearings on each of said arms 22. The lower feed roller 2'7 is stationarily .-mounted on the bearing, while the upper roller 28 may be vertically adjusted by a screw 29 to regulate it with respect to theroller 27, according to the thickness of the sheet material m passing therebetween. The ends of said feeding rollers are provided with inter-meshing gears 27a and 2812, as shown in Figure 4, by which both of said rollers are positively operated in unison.

In order to effect this positive operation, the shaft 30 of the lower roller 2'7 projects outwardly for a distance and has mounted thereon a pawl and ratchet feeding mechanism connected to the crank arm 31 eccentrically connected at 32 to one end of the shaft'13.

The pawl and ratchet mechanism above referred to comprises a ratchet wheel 33 keyed or otherwise made fast on the shaft 30. The pawl 34 overlies its periphery and is plvotally mounted on a disc 35, preferably in juxta-relation with said ratchet and loosely mounted on said shaft 30. One end of said crank arm 31 is pivotally secured to said disc at a point adjacent its periphery, as at 36. Thus, it will be seen thatas the shaft 13 is rotated the crank arm 31 is reciprocated, which causes the disc 35 to be oscillated on the shaft 30 and in consequence will cause the pawl 34 to be oscillated with respect to the periphery of the ratchet wheel 33, thus advancing the ratchet wheel in the direction ofthe arrow shown in Figure 3 in one direction of the oscillating movement of the pawl. The pawl 34 may be held in engagement with the ratchet wheel by a spring 37. The winding beam 25 onthe forward end of the bed may be correspondingly rotated and in unison with the feed rollers 27 and 28 through the means of a belt 38, trained over a pulley .wheel 39 on the end of the shaft 30 and'a pulley wheel 40 on the end of said beam 25. Thus it will be manifest that the material m from said rollers will be positively advanced step by step between the tool-heads 20 and 21 and the parts are so .arranged and timed that the feeding of the material between said heads will be-accomplished when said tool-heads have been separated by the upward movement of the punching machine cross-head 14, and will be at rest when said tool-heads have been brought together in contact with the strip. I

The degree of throw or movement of the ratchet wheel 33 can be readily adjusted by radial movement of the end 32 of the crank. rod 31 in the guideway 41 provided on the enlarged or disked end of the shaft 13. The drive shaft 13 of the punching machine may be operated in any suitable manner. However, a fly wheel 42 is provided on one end thereof and may have a pulley belt trained around its periphery.

Tool-heads 20 and 21 each comprise a flat plate, preferably of metal, the uppertool-head having a shank 19 projecting from medial portion of its upper face, to be received in the chuck of the cross-head 14, while the lower tool-head rests flat upon the bed of the machine and at its forward corner portions has upwardly, extending guide posts 43, which are received in openings 44 extending through corresponding portions of the upper tool holder 20. These openings 44 are lined with bushings 45 having a tight but slidable fit with the guide posts 43, which latter are preferably grooved at their upper ends to receive graphite or any other lubricant material, thus when the tool holders are moved together, perfect alignment is insured between the punches and dies carried by the respective heads.

The purpose of the presentinvention, as above stated, is to provide the sheet m of the material with a plurality of closely associated perforations, from the edges of which perforations extend burrs or tangs which project either from one side of the sheet or from opposite sides of the sheet, according to the specific use for which the perforated material is to be used. In those instances where it is desired to have the burrs or tangs projecting from opposite sides of the sheet, this is best accomplished for practical operation by having adjacent punches arranged on opposite sides of the sheet, thus providing the burrs on the side opposite that from which it is punched. Also, these punches may be arranged on the respective tool-heads in alternating rows, or they may be arranged in staggered rows, as desired.

In the present showing, the tool-heads have the punch elements arranged thereon to provide the perforations p with the burrs n projecting from opposite sides of the sheet in alternating rows.

Each tool-head 20 and 21 has mounted thereon a punch and die unit 50 and 51, respectively, and, since each are of the same construction, description of one will sufiice for the other. The punch and die devices each consisted of a punch r holder in the form of a plate e having a plurality of closely associated bores or sockets I there- 1 through, and through which the body of the punch extends and is retained. The punch ele-- ments 52, shown in detail in Figures llto 13 inclusive, each comprise an elongated cylindrical body a having an enlarged angularly shaped head b at one end and at its other end an elongated reduced shank 6 pointed in any suitable manner to provide the penetrating end of the punch. This punching end is preferably formed by bevelling its extremity d on two oppositesides, each of said bevelled surfaces being of different degrees of angularity with respect to the axis of the ,punch element 52. v

The angular heads of the punch elements 52 are received in milled grooves g on the outer or back faces of the plate e (see Figures 8 and 9) so as to prevent the punches 52 from rotating in the sockets f and thus retain the punch extremities at the angle desired, with respect to the sheet material m.

Each punch holder e has associated with it a die-plate It provided with a plurality of apertures .i therein, corresponding to the number of punch elements 52 of its respective punch holder and in which the shanks c of said punches normally slidably extend with their punching ends 11 normally retained within said apertures or at least flush with the outer surface thereof, as clearly shown in Figures 6 and 8. The die-plate h is also providedwith a plurality of female die openings 7' positioned therein corresponding with the punch elements 52 of the opposite punch device and to receive and cooperate with said opposite punch element during the punching operation, as clearlyshown in' Figure '7, to produce said perforations 12 without removing the material from the openings forming the perforations, thus providing the burrs and tangs 12' about the edges thereof.

The die-plate is yieldably mounted on its respective punch holder plate e by means of compression springs 53 interposed between the plates at their edges and having their ends retained in sockets is formed in said edge portions of said plates. The springs 53 normally maintain these plates 6 and h separated and normally urge the die-plates h to move outwardly of the punch 52, thus serving as a stripper as the punch units 50 and 51 are separated during the operation of the machine.

In order to prevent any lateral movement between holder plate e and h, the die-plate is formed on its inner face with a recess 54, in

which a corresponding projection 58. on the inner. face of said punch plate slidably fits and extends.

Each unit assembly 50 and 51 is held on its respective tool-head 20 or 21 by bolts 55 slidably extending through said tool-head and through openings 56 in the holder plate e and'threadedly secured in threaded openings 57 in the die-plate. Thus, it will be obviousthat in their normal position the die-plates are moved and held spaced from the punch plates 6 by the springs 53, which movement and spacing is limited by the heads of the bolts 55 and which may be varied by adjustment of said bolts in the threaded opening 57 of the die-plates. It is preferred that in normal position, the punch ends of the punches will lie'within the apertures 2' of the die-plates.

After the punching operation, the upper toolhead 20 is raised by the cross-head 14, and simultaneously with this upward movement of the cross-head, the pitman rod 31 will actuate the disc 35 and move the pawl 34 to advance the ratchet 33, thus operating the feed rollers 2'7 and 28 to advance the sheet material m to bring an unpunched area thereof between the punch units 50 and 51 of the machine, as clearly shown in Figure 6. At the same time the winding beam 25 will be actuated through the belt 38 to take up the slack in the sheet material and to hold the sheet taut. Further rotation of the shaft 13 moves the cross-head 14 and tool-head 20 downwardly, bringing the punch unit 50 down upon the unit 51 with the sheet material therebetween, as clearly shown in Figures 6 and 8. Still further downward movement of the cross-head 14 will cause die-plates h of both punch united 50 and 51 to be compressed against springs 53 and the punching ends at of the punchers 52 of both punch units will penetrate the sheet in a manner to form the perforations p with their burrs n, as above described. Further movement of the shaft 13 causes the tool-head 20 to be raised to the position show'n'i'n Figure 5, during which latter opera tion the die-plates e under the influence of the springs 53 will move outwardly from their respective punch holders and outwardly along the shanks c of the punch elements 52, thus stripping the perforated material 112. from the punch elements. The cycle of operation is then repeated continuously until all of the material, or so much as desired, has been perforated.

To further insure proper alignment of each punch holding-plate with its respective die-plate, each end of the punch plates is provided with a guide projection 65, which has sliding fit with corresponding openings 66 in the ends of the die-plates.

Of course, it will be understood that if a sheet of material is to be perforated with the burrs or tangs n extending only from one side of the sheet, the punches will be provided only in one of said punch plates. It will also be observed that the die-plates are cut away at the forward edge of their opposite surfaces, as at 67, to form a clearance, through which the perforated plate may pass without deforming .or mashing the burrs or tangs which have been formed.

Furthermore, it will be observed that when the roll of sheet material from the coil s has become exhausted and the perforating operation of the entire sheet being completed,,the reel r of the perforated material may be removed from one end of the beam 25 by merely sliding it therefrom; In the foregoing description and drawings, the invention has been disclosed in the form in which it is considered practical.- I-Iowever, the invention is not limited to this form, as it may be embodied in other forms; thus, it is to be understood that the invention is to only be limited by the terms of the appended claims.

What is claimed is:

1. The combination, in a sheet prick-punching machine, of opposed tbol-heads, each having a plurality of punching elements thereon, a yieldable die-plate for each tool-head and having dieopenings therein to cooperate with the punches of the opposing tool-head, actuating means having operative connection with at least one of said toolheads to intermittently bring said tool-heads on opposite sides of the material to be punched, said punching elements and die-openings being such as to form perforations in said material with lateral projections at the edges of said perforations,

and intermittent means for moving the sheet of material between said tool-heads when the latter are out of punching position.

2. The combination, in a sheet prick-punching machine, of opposed tool-heads, each having a plurality of punching elements thereon, a dieplate on each tool-head and yieldably mounted thereon and adapted to contact with the material to be punched, said die-plates having openings therein through which punching elements of their respective tool-head slidably extend and normally lie, whereby said plates strip their respective punching element when said tool-heads are out of punching position, actuating means having operative connection with at least one of said tool-heads, whereby the latter are intermittently brought into opposed punching relation with respect to each other, and intermittent feeding means for moving the sheet of material between said tool-heads when said tool-heads are out of punching position.

3. The combination, in a sheet prick-punching machine, of opposed tool-heads, each having a die-openings therein to cooperate with the punching elements of the opposing tool-head to form perforations in said material with lateral projections at the edges thereof, and intermittent feedopenings therein in which the penetrating ends of said elements are normally housed and through which said ends project when said stripper plate and said die-plate are brought into compressed contact with the material to be punched.

5. In a sheet perforating machine adapted to be brought into and out of opposed punching relation, each of said heads having a plurality of punching elements thereon, yieldably mounted die-plates on their opposing faces, said die-plates having die openings to receive and cooperate with the punch elements on the opposing head, said die-plates also having openings therein in which the penetrating ends of said elements are normally housed and through which said ends project when said plates are brought into compressed contact with the material to be punched.

6. In a sheet perforating machine as set forth in claim 5, further characterized by corresponding and fitted projections and recesses on the opposing faces of said plates and 'said toolheads whereby the proper alignment of the die-openings and punching elements of opposing heads may be maintained.

. MARTIN D. FITZGERALD. 

